MUSTANG BIO, INC. (MBIO) stock intrinsic value fair value estimate & owner earnings analysis

Mustang Bio is a clinical-stage cancer drug developer that is majority-controlled by Fortress Biotech. It has no approved product and no sales. Its lead program, MB-109, combines a CAR T-cell therapy (MB-101) with an oncolytic virus (MB-108) for recurrent glioblastoma and high-grade astrocytoma. The FDA cleared the trial application in October 2023 and granted orphan drug designation to MB-108 in November 2024 and to MB-101 in July 2025. The company has ended the lease on its cell-processing facility in Worcester, Massachusetts, and is exploring a single-institution study at City of Hope that could start in the second quarter of 2026. That study is still only being explored, so it earns no credit here. What the shares are worth today is mostly what is left of the cash. At June 30, 2026 the company held $15.2 million in cash against $8.1 million of liabilities, leaving about $7.5 million of equity for roughly 6.7 million shares, or about $1.12 a share before any further spending. The business itself has never produced positive owner earnings. On our measure (operating cash flow, less working-capital swings, less shares issued in place of cash pay such as Fortress fees and stock compensation, less equipment spending) the loss was about $4.4 million in 2025, $13.7 million in 2024 and $47.7 million in 2023. The 2025 loss was 68% smaller than 2024, because the company cut costs and settled old payables for about $2.1 million less than owed. In the first half of 2026 operations used another $2.0 million in cash. We do not credit any future growth: no drug is approved, no partner has committed to pay, and cost-cutting is not earnings. Base case, about $0.05 a share. Spending continues at the first-half 2026 pace of roughly $4 million a year for two years while the program stays unproven. Discounted at 6%, that spending consumes almost all of the $7.5 million of equity, leaving about $0.3 million. We assign nothing to MB-109 itself, because there is no signed partner, no approved product and no revenue behind it. Bear case, $0. Spending stays at the 2025 level of about $5.3 million a year. At that pace the equity would be used up in roughly a year and a half, and any further funding would have to come from selling more shares at low prices, which dilutes existing holders. The company carries no borrowings, so we do not see it owing more than it is worth. Shareholders simply keep nothing from the current balance sheet. Bull case, about $0.57 a share. Management spends about $4 million over the next year, at the current pace, and then winds the company down to its remaining cash. On that path $7.5 million less about $3.7 million of discounted spending is $3.8 million, or about $0.57 a share. We include no value for the drug program, since none of its milestones has been achieved. Points to know. The company disclosed substantial doubt about its ability to continue as a going concern in its 2024 financial statements and its September 2025 quarterly report. It removed that statement in its 2025 annual report, after raising about $14.5 million in 2025 from share sales and warrant exercises and cutting costs, and said it has cash to fund operations for at least twelve months from that filing. The company also fell short of Nasdaq listing standards in 2024 and early 2025, carried out a 1-for-50 reverse stock split in January 2025, and later regained compliance. Our per-share loss figures for earlier years are restated for that split and for the earlier 1-for-15 split in April 2023, so they look very large. The 2022 share count is the company's own later restated figure, and it does not tie exactly to the count originally reported for that year; we could not reconcile the difference from the filings. Accounting judgements: shares issued to Fortress as fees or dividends, and stock compensation, are treated as real costs even though no cash leaves. Cash paid to acquire research licenses is not treated as equipment spending. What would make this too low: a partner agreeing to fund the glioblastoma program, or positive early data from a City of Hope study. What would make it too high: further share sales, or spending above the current pace.